Because of rising fuel costs, there is a persistent problem of preventing a thief from siphoning fuel from a parked vehicle. Large over-the-road trucks may carry hundreds of gallons of diesel fuel. If parked in an accessible location, a would-be thief need only insert a siphon tube into the fuel tank and create a vacuum to establish a flow from the tank to some other storage container. Thus, a length of flexible tubing and a container are virtually all the thief needs.
Because of the ease by which such fuel may be siphoned, it has been known to permanently mount an anti-siphon screen in the fillneck of such a fuel tank. Traditionally, the fillneck is simply welded to the fuel tank, and a portion of the fillneck extends within the tank's interior. The conventional anti-siphon screen surrounds a portion of the inner end of the fillneck (i.e., the end within the tank), and is suitably welded thereto. While effective, this required that the fillneck screen have been applied when the tank was originally manufactured. Existing tanks could not be retrofitted with an after-market fillneck screen. Moreover, should the fillneck screen become damaged for any reason, it could not be readily repaired.
Accordingly, there is believed to be a clear and present need for an improved anti-siphon fillneck screen which can be quickly and removably mounted on a liquid storage tank.